Dipole antennas are well known in the art. Monopole antennas are well known in the art. A combination of a dipole antenna and a monopole antenna are known from e.g. U.S. Pat. No. 5,313,218 which discloses an antenna assembly including a dipole antenna and a monopole antenna having substantially perpendicular polarization directions. The dipole antenna is provided with a balun a portion of which serves as a backplane for a micro strip transmission line which transmits RF signals. The micro strip transmission line includes a first portion connected to a coaxial feed cable, a second portion having its ends respectively connected by a first switch to the monopole antenna and a second switch to the balun portion and a third portion. Closing the switches renders the monopole antenna operative. The third portion serves to detune the dipole antenna.
U.S. Pat. No. 7,289,080 disclose an antenna of dipole and monopole antenna elements with filtering to achieve a greater bandwidth. The multiple antenna elements are isolated or combined in order to provide a self adjusting electrical length by using multiterminal filtering.
Patent application US 2011/0163928 discloses an antenna comprising a monopole and a dipole. The dipole provides a first antenna element and a second antenna element, which provide a common longitudinal axis with the longitudinal axis of a monopole. The first antenna element of the dipole is connected to the second antenna element of the dipole and to the monopole. The monopole bears the dipole. The antenna further contains a decoupling element, which is disposed between the monopole and the dipole.